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A034674
Sum of n-th powers of divisors of 128.
3
8, 255, 21845, 2396745, 286331153, 35468117025, 4467856773185, 567382630219905, 72340172838076673, 9241421688590303745, 1181745669222511412225, 151189550474521284184065, 19347536633519984760328193
OFFSET
0,1
LINKS
Quynh Nguyen, Jean Pedersen, and Hien T. Vu, New Integer Sequences Arising From 3-Period Folding Numbers, Vol. 19 (2016), Article 16.3.1. Cites this sequence.
FORMULA
a(n) = (2^(8*n) - 1)/(2^n - 1). Exp( Sum_{n >= 1} a(n)*x^n/n ) = 1 + 255*x + 43435*x^2 + ... is the o.g.f. for the 7th subdiagonal of triangle A022166, essentially A022190. - Peter Bala, Apr 07 2015
MATHEMATICA
Total[#^Range[0, 20]&/@Divisors[128]] (* Vincenzo Librandi, Apr 17 2014 *)
PROG
(Magma) [DivisorSigma(n, 128): n in [0..20]]; // Vincenzo Librandi, Apr 17 2014
CROSSREFS
Sequence in context: A171612 A053717 A267250 * A317511 A300176 A372670
KEYWORD
nonn,easy
STATUS
approved